Suspect’s Mental Ability Is at Fore as Jurors in Patz Trial Prepare to Get Case

After 10 weeks of testimony, both sides rested on Thursday in the trial of the former store clerk charged with killing 6-year-old Etan Patz. Closing arguments in the case are set for Monday.

On Thursday, the prosecution called as its last witness a woman who dated the defendant, Pedro Hernandez, when they were both teenagers. Like several other prosecution witnesses, the woman, Yvonne Velez, 51, said that Mr. Hernandez had not shown any obvious symptoms of mental illness while growing up in Camden, N.J.

Mr. Hernandez’s fate could well turn on how the jury of seven men and five women judge his mental competence. The prosecution’s case largely rests on taped confessions he gave to investigators in May 2012 after a six-and-a-half-hour interrogation.

But defense lawyers say those statements were fictions invented by a man with a weak and troubled mind. They have presented evidence that Mr. Hernandez has a low I.Q. and a personality disorder that make it difficult for him to distinguish fantasy from reality. His daughter, Becky, testified that he had frequent hallucinations and exhibited odd, paranoid beliefs during the several years before he confessed to the killing.

Prosecutors have presented evidence that Mr. Hernandez, 54, never complained about hallucinations and did not show signs of intellectual impairment before applying for disability benefits in the early 1990s and being referred to a psychiatrist. Joan Illuzzi-Orbon, the lead prosecutor in the case, has suggested that Mr. Hernandez is feigning or exaggerating his mental disabilities.

Mr. Hernandez’s lawyer, Harvey Fishbein, said on Thursday that even though prosecution witnesses who knew his client socially had testified about his apparent mental acuity, they had all missed signs of his underlying illness, schizotypal personality disorder.

“By trying to have witnesses describe an extreme psychiatric disorder, which we’re not claiming our client has, is extremely misleading,” Mr. Fishbein said outside the courtroom.

The National Institutes for Health notes that schizotypal personality disorder “should not be confused with” schizophrenia. “People with schizotypal personality disorder can have odd beliefs and behaviors,” the agency explains on its website. “But unlike people with schizophrenia, they are not disconnected from reality.”

Mr. Hernandez was arrested in May 2012 after his brother reported to the police that he had told his ex-wife and members of a church group that he had killed a child in New York City in the late 1970s.

Etan disappeared on May 25, 1979, as he was walking from his parent’s loft in SoHo to a school bus stop two blocks away. He was last seen headed toward a bodega near the bus stop to buy a soda.

Mr. Hernandez worked as a clerk in the bodega at the time. He told detectives he had lured the boy into the store’s basement with the promise of a soda, then strangled him, put him in a plastic bag and box, and left him in a subterranean passageway a block and a half away, on Thompson Street.

Etan’s body has never been found. His father, Stanley Patz, was in the courtroom on Thursday. He shook his head and shrugged as prosecutors played recordings of four phone calls that Mr. Hernandez made to his wife and daughter in 2012 and 2013, when he was in jail. His words were mostly unintelligible, and only jurors were given transcripts of the calls.

Mr. Hernandez sat in a gray shirt and tie and dun-colored slacks, his shoulders drooped. When his voice played over the speakers, he rubbed his face.

In one exchange that could be heard clearly, Mr. Hernandez asked his daughter for spiritual support. “I need you to pray for me, O.K.?” he said. “I’m going to need you to help me out because I have a big problem here.”

The jury is expected to begin deliberations on Tuesday.

Correction:

An article in some editions on Friday about the final day of testimony in the trial of Pedro Hernandez, who is charged with murder in the 1979 disappearance of Etan Patz, 6, erroneously included one of Etan’s relatives among those who were in the courtroom. Julie Patz, his mother, was not in attendance.

A version of this article appears in print on , on Page A20 of the New York edition with the headline: Suspect’s Mental Ability Is at Fore as Jurors in Patz Trial Prepare to Get Case. Order Reprints | Today’s Paper | Subscribe